Google has filed a patent for a “'needle-free blood draw” smartwatch: it could be wearable or hand-held, and may eventually replace blood glucose meters.

The device sends an "abrupt surge" of gas into a barrel that has a “micro-particle” that punctures the skin and takes a tiny amount of blood. When the droplet is formed, it is sucked into a negative pressure barrel.

"Such an application might be used to draw a small amount of blood, for example, for a glucose test," the patent reads.

The blood-sucking smartwatch would also cause as little pain as possible, even compared with the current glucose meters that ‘pin prick’ your finger.

It remains unclear when and whether the device will hit the market, but it’s not Google’s first attempt to reach out to diabetics.

Google – along with the Pharmacy giant Novartis – is now developing smart contact lenses, wirelessly connected to mobile devices, that will monitor blood sugar levels, and another lens set to treat far-sightedness.

The technology involves non-invasive sensors, microchips and other mini-electronics embedded within the lens.

Google said there may be other uses for the smart lenses, and only recently sent a patent for a lens with a built-in camera.

In other health care tech novelties, Google launched its Google Fit application that puts the user’s health characteristics from various devices and applications into one place.

The World Health Organisation estimates that 9 percent of adults over 18 years old live with diabetes, and 1.5 million people died from by the disease in 2015 alone.